Hazardous Air Pollutants List and Reporting Thresholds

DEP Rules, Chapter 137, "Emission Statements," Appendix A establishes the list of chemicals and compounds regulated as hazardous air pollutants in Maine. Facilities must report emissions of the following hazardous air pollutants when any of the following occur:

the facility emits to the air any hazardous air pollutant at or above the threshold listed below;
where actual emissions are not known, the facility either uses, processes, or manufactures any hazardous air pollutant at or above the threshold listed below;
the facility releases to a municipal sewer system (POTW) any hazardous air pollutant that has a vapor pressure greater than 0.1 mm Hg at or above the threshold listed below; or
in the aggregate, a facility emits to the air or releases to a municipal sewer system any hazardous air pollutant at or above the threshold listed below.

Consolidated Pollutant List, including HAP Reporting Thresholds, in Microsoft Excel Format (51 Kb, updated 3/17/2005)! Search by pollutant code or pollutant name - sort the way you want to see the data!

Satellite i-STEPS Pollutant Code	Pollutant Name	Reporting Threshold (lbs.)
Jump To Pollutant A-D E-M N-Z
75070	Acetaldehyde	1,000
60355	Acetamide	1,000
108247	Acetic Anhydride	2,000
67641	Acetone	20,000
75058	Acetonitrile	2,000
98862	Acetophenone	2,000
53963	2-Acetylaminofluorene	2,000
107028	Acrolein	10
79061	Acrylamide	200
79107	Acrylic Acid	200
107131	Acrylonitrile	1,000
107051	Allyl Chloride	200
ALUMCOMP	Aluminum Fume or Dust	1,000
92671	4-Aminobiphenyl	2,000
NH3	Ammonia (also a Criteria Air Pollutant)	2,000
62533	Aniline	200
90040	o-Anisidine	200
92	Antimony and Antimony Compounds	200
93	Arsenic and Arsenic Compounds (also inorganic arsine)	20
1332214	Asbestos	10
BARICOMP	Barium and Barium Compounds	2,000
71432	Benzene	1,000
92875	Benzidine	10
98077	Benzotrichloride	20
50328	Benzo[a]pyrene	1,000
191242	Benzo[g.h.i]perylene	10
100447	Benzyl Chloride	1,000
109	Beryllium and Beryllium Compounds	20
92524	Biphenyl	2,000
117817	Bis(2-ethylhexyl)phthalate	2,000
542881	Bis(chloromethyl)ether	10
75252	Bromoform	2,000
106990	1,3-Butadiene	200
71363	N-Butanol	2,000
123864	N-Butyl Acetate	20,000
75650	tert-Butyl Alcohol	2,000
125	Cadmium and Cadmium Compounds	10
156627	Calcium Cyanamide	1,000
133062	Captan	2,000
63252	Carbaryl	2,000
75150	Carbon Disulfide	2,000
56235	Carbon Tetrachloride (also a Greenhouse Gas)	1,000
463581	Carbonyl Sulfide	1,000
120809	Catechol	2,000
133904	Chloramben	2,000
57749	Chlordane	10
7782505	Chlorine	200
10049044	Chlorine Diozide	200
79118	Chloroacetic Acid	1,000
532274	2-Chloroacetophenone	10
108907	Chlorobenzene	2,000
510156	Chlorobenzilate	1,000
67663	Chloroform (also a Greenhouse Gas)	1,000
107302	Chloromethyl Methyl Ether	200
126998	Chloroprene	200
136	Chromium and Chromium Compounds (including hexavalent chromium)	10
139	Cobalt and Cobalt Compounds	10
140	Coke Oven Emissions	200
COPPCOMP	Copper and Copper Compounds	1,000
95487	o-Cresol	2,000
108394	m-Cresol	2,000
106445	p-Cresol	1,000
1319773	Cresols and Cresylic Acid	2,000
98828	Cumene	2,000
144	Cyanide Compounds	1,000
110827	Cyclohexane	20,000
94757	2,4-D, salts and esters	2,000
3547044	DDE	2,000
334883	Diazomethane	2,000
132649	Dibenzofuran	2,000
96128	1,2-Dibromo-3-Chloropropane	20
84742	Dibutylphthalate	2,000
106467	1,4-Dichlorobenzene	2,000
95501	1,2-Dichlorobenzene	2,000
91941	3,3-Dichlorobenzidine	200
111444	Dichloroethyl Ether	2,000
542756	1,3-Dichloropropene	1,000
62737	Dichlorovos	200
111422	Diethanolamine	20
121697	N,N-Diethyl Aniline	1,000
64675	Diethyl Sulfate	200
DIISCOMP	Diisocynates	2,000
119904	3,3-Dimethoxybenzidine	2,000
60117	Dimethyl Aminoazobenzene	200
119937	3,3'-Dimethyl Benzidine	20
79441	Dimethyl Carbomoyl Chloride	2,000
68122	Dimethyl Formamide	2,000
57147	1,1-Dimethyl Hydrazine	200
131113	Dimethyl Phthalate	1,000
77781	Dimethyl Sulfate	1,000
534521	4,6-Dinitro-o-Cresol	200
51285	2,4-Dinitrophenol	1,000
121142	2,4-Dinitrotolune	1,000
123911	1,4-Dioxane	2,000
155	Dioxin and Dioxin-like Compounds**	0.0002
122667	1,2-Diphenylhydrazine	200
Jump To Pollutant A-D E-M N-Z		top of page
106898	Epichlorohydrin	200
106887	1,2-Epoxybutane	2,000
141435	Ethanolamine	2,000
110805	2-Ethoxyethanol	2,000
141786	Ethyl Acetate	20,000
140885	Ethyl Acrylate	2,000
100414	Ethyl Benzene	2,000
51796	Ethyl Carbamate (Urethane)	200
75003	Ethyl Chloride (Chloroethane)	20,000
106934	Ethylene Dibromide (Dibromomethane)	10
107062	Ethylene Dichloride (1,2-Dichloroethane)	1,000
107211	Ethylene Glycol	2,000
151564	Ethylene Imine (Aziridine)	2,000
75218	Ethylene Oxide	200
96457	Ethylene Thiourea	200
75343	Ethylene Dichloride	2,000
383	Fine Mineral Fibers	2,000
50000	Formaldehyde	1,000
64186	Formic Acid	20,000
76131	Freon 113 (Trichlorotrifluoroethane) (also a Greenhouse Gas)	2,000
98011	Furfural	2,000
171	Glycol Ethers	2,000
76448	Heptachlor	10
118741	Hexachlorobenzene	10
87683	Hexachlorobutadiene	200
77474	Hexachlorocyclopentadiene	200
67721	Hexachloroethane	1,000
822060	Hexamethylene-1,6-Diisocynate	20
680319	Hexamethylphosphoramide	2,000
110543	Hexane	2,000
302012	Hydrazine	20
7647010	Hydrochloric Acid (acid aerosol only)	2,000
7664393	Hydrogen Fluoride (Hydrofluoric Acid)	1,000
7783064	Hydrogen Sulfide	200
123319	Hydroquinone	1,000
78591	Isophorone	20,000
67630	Isopropyl Alcohol (used in strong acid manufacturing processes)	20,000
195	Lead and Lead Compounds	100
58899	Lindane	200
108316	Maleic Anhydride	1,000
198	Manganese and Manganese Compounds	20
199	Mercury and Mercury Compounds	10
67561	Methanol	2,000
72435	Methoxychlor	100
109864	2-Methoxyethanol	2,000
96333	Methyl Acrylate	2,000
74839	Methyl Bromide (Bromomethane) (also a Greenhouse Gas)	1,000
74873	Methyl Chloride (also a Greenhouse Gas)	2,000
71556	Methyl Chloroform (1,1,1-Trichloroethane) (also a Greenhouse Gas)	2,000
78933	Methyl Ethyl Ketone (2-Butanone)	2,000
60344	Methyl Hydrazine	200
74884	Methyl Iodide (Iodomethane)	1,000
108101	Methyl Isobutyl Ketone	2,000
624839	Methyl Isocyanate	200
74931	Methyl Mercaptan	1,000
80626	Methyl Methacrylate	2,000
872504	N-Methyl-2-Pryyolidone	2,000
1634044	Methyl Tert Butyl Ether	20,000
101144	4,4,-Methylene Bis(2-Chloroaniline)	200
75092	Methylene Chloride (Dichloromethane) (also a Greenhouse Gas)	2,000
101688	Methylene Diphenyl Diisocyanate	200
1313275	Molybdenum Trioxide	200
101779	4,4'-Methylenedianiline	200
Jump To Pollutant A-D E-M N-Z		top of page
91203	Napthalene	1,000
226	Nickel and Nickel Compounds	20
7697372	Nitric Acid	1,000
98953	Nitrobenzene	1,000
92933	4-Nitrobiphenyl	200
100027	4-Nitrophenol	1,000
79469	2-Nitropropane	20
684935	N-Nitroso-N-Methylurea	2,000
62759	N-Nitrosodimethylamine	10
59892	N-Nitrosomorpholine	20
144627	Oxalic Acid	2,000
56382	Parathion	1,000
82688	Pentachloronitrobenzene	1,000
87865	Pentachlorophenol	1,000
108952	Phenol	2,000
106503	p-Phenylendiamine	2,000
75445	Phosgene	200
7803512	Phosphine	200
7723140	Phosphorus	20
85449	Phthalic Anhydride	2,000
1336363	Polychlorinated Biphenyls	10
246	Polycyclic Organic Matter	100
1120714	1,3-Propane Sultone	200
57578	Beta-Propiolacetone	2,000
123386	Propionaldehyde	2,000
114261	Propoxur (Baygon)	1,000
78875	Propylene Dichloride (1,2-Dichloropropane)	1,000
75558	1,2-Propylenimine(1-Methyl Aziridine)	10
91225	Quinoline	200
106514	Quinone	200
400	Radionuclides (including radon)	2,000
253	Selenium and Selenium Compounds	200
100425	Styrene	2,000
96093	Styrene Oxide	2,000
7664939	Sulfuric Acid (acid aerosol only)	1,000
79345	1,1,2,2,-Tetrachloroethane	2,000
127184	Tetrachloroethylene (Perchloroethylene)	2,000
10999	Tetrahydrofuran	2,000
13463677	Titanium Dioxide (Titanium Oxide)	2,000
7550450	Titanium Tetrachloride	20
108883	Toluene	2,000
95807	2,4-Toluene Diamine	200
584849	2,4-Toluene Diisocyanate	20
95534	o-Toluidine	1,000
8001352	Toxaphene (Chlorinated Camphene)	10
120821	1,2,4-Trichlorobenzene	10
79005	1,1,2-Trichloroethane	1,000
79016	Trichloroethylene	2,000
88062	2,4,6-Trichlorophenol	2,000
95954	2,4,5-Trichlorophenol	2,000
121448	Triethylamine	1,000
1582098	Trifluralin	100
95636	1,2,4-Trimethyl Benzene	1,000
520841	2,2,4-Trimethylpentane	2,000
8006642	Turpentine	2,000
VANCOMP	Vanadium Compounds	2,000
108054	Vinyl Acetate	2,000
593602	Vinyl Bromide	1,000
75014	Vinyl Chloride	200
75354	Vinylidene Chloride (1,1-Dichloroethylene)	1,000
106423	p-Xylenes	2,000
95476	o-Xylenes	2,000
108383	m-Xylenes	2,000
1330207	Xylenes (isomers and mixture)	2,000
ZINCCOMP	Zinc and Zinc Compounds	2,000

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** For the purpose of this definition, "Dioxin and Dioxin-like Compounds" means specific compounds in the following chemical classes that are "Dioxin-like:" polychlorinated dibenzo-p-dioxins (PCDDs or CDDs); polychlorinated dibenzofurans (PCDFs or CDFs); polybrominated dibenxo-p-dioxins (PBDD or BDDs); polybrominated dibenzofurans (PBDFs or BDFs); and polychlorinated biphenyls (PCBs). "Dioxin-like" means those compounds that have a similar chemical structure and similar physical-chemical properties as 2,3,7,8-tetrachlorodibenzo-p-dioxin, and therefore, induce a similar toxic response. Because of their hydrophobic nature and resistance towards metabolism, these chemicals persist and bioaccumulate in fatty tissues of animals and humans. The seven dioxin-like CDDs, seven dioxin-like BDDs, ten dioxin-like CDFs, and ten dioxin-like BDFs are the congeners that have chlorine/bromine substitutions in, at a minimum, the 2,3,7 and 8 positions. Additionally, 13 PCB congeners have dioxin-like toxicity; these are PCBs with four or more lateral chlorines with one or no substitution in the ortho position. These compounds are sometimes referred to as "coplanar," meaning that they can assume a flat configuration with rings in the same plant. Mixed chlorinated and brominated congeners of dioxins, furans, and biphenyls may also meet the definition of "dioxin-like." "Dioxin and Dioxin-like Compounds" includes the following specific dioxin congeners, furan congeners, and dioxin-like PCBs.

Chemical Notation	Isomer Group	IUPAC No.(a)
Dioxin Congeners
2,3,7,8-TCDDs	The isomers of tetrachlorodibenzo-p-dioxin with chlorine substitutions in the 2,3,7,8 positions
1,2,3,7,8-PeCDDs	The isomers of pentachlorodibenzo-p-dioxin with chlorine substitutions in the 1,2,3,7,8 positions
1,2,3,4,7,8-HxCDDs	The isomers of hexachlorodibenzo-p-dioxin with chlorine substitutions in the 2,3,7,8 positions
1,2,3,6,7,8-HxCDDs	The isomers of hexachlorodibenzo-p-dioxin with chlorine substitutions in the 1,2,3,6,7,8 positions
1,2,3,7,8,9-HxCDDs	The isomers of hexachlorodibenzo-p-dioxin with chlorine substitutions in the 1,2,3,7,8,9 positions
1,2,3,4,6,7,8-HpCDDs	The isomers of heptachlorodibenzo-p-dioxin with chlorine substitutions in the 1,2,3,4,6,7,8 positions
OCDDs	The isomers of octachlorodibenzo-p-dioxin with chlorine substitutions in any positions
Furan Congeners
2,3,7,8-TCDFs	The isomers of tetrachlorodibenzofuran with chlorine substitutions in the 2,3,7,8 positions
1,2,3,7,8-PeCDFs	The isomers of pentachlorodibenzofuran with chlorine substitutions in the 1,2,3,7,8 positions
2,3,4,7,8-PeCDFs	The isomers of pentachlorodibenzofuran with chlorine substitutions in the 2,3,4,7,8 positions
1,2,3,4,7,8-HxCDFs	The isomers of hexachlorodibenzofuran with chlorine substitutions in the 1,2,3,4,7,8 positions
1,2,3,6,7,8-HxCDFs	The isomers of hexachlorodibenzofuran with chlorine substitutions in the 1,2,3,6,7,8 positions
1,2,3,7,8,9-HxCDFs	The isomers of hexachlorodibenzofuran with chlorine substitutions in the 1,2,3,7,8,9 positions
2,3,4,6,7,8-HxCDFs	The isomers of hexachlorodibenzofuran with chlorine substitutions in the 2,3,4,6,7,8 positions
1,2,3,4,6,7,8-HpCDFs	The isomers of heptachlorodibenzofuran with chlorine substitutions in the 1,2,3,4,6,7,8 positions
1,2,3,4,7,8,9-HpCDFs	The isomers of heptachlorodibenzofuran with chlorine substitutions in the 1,2,3,4,7,8,9 positions
OCDFs	The isomers of octachlorodibenzofuran with chlorine substitutions in any position
Dioxin-like PCBs
3,3',4,4'-TeCB	tetrachlorinated biphenyls with chlorine substituted in the 3,3',4,4' positions	PCB-77
3,4,4',5-TCB	tetrachlorinated biphenyls with chlorine substituted in the 3,4,4',5 positions	PCB-81
2,3,3',4,4'-PeCB	pentachlorinated biphenyls with chlorine substituted in the 2,3,3',4,4' positions	PCB-105
2,3,4,4',5-PeCB	pentachlorinated biphenyls with chlorine substituted in the 2,3,4,4',5 positions	PCB-114
2,3',4,4',5-PeCB	pentachlorinated biphenyls with chlorine substituted in the 2,3',4,4',5 positions	PCB-118
2',3,4,4',5-PeCB	pentachlorinated biphenyls with chlorine substituted in the 2',3,4,4',5 positions	PCB-123
3,3',4,4',5-PeCB	pentachlorinated biphenyls with chlorine substituted in the 3,3',4,4',5 positions	PCB-126
2,3,3',4,4',5-HxCB	hexachlorinated biphenyls with chlorine substituted in the 2,3,3',4,4',5 positions	PCB-156
2,3,3',4,4',5'-HxCB	hexachlorinated biphenyls with chlorine substituted in the 2,3,3',4,4',5' positions	PCB-157
2,3',4,4',5,5'-HxCB	hexachlorinated biphenyls with chlorine substituted in the 2,3',4,4',5,5' positions	PCB-167
3,3',4,4',5,5'-HxCB	hexachlorinated biphenyls with chlorine substituted in the 3,3',4,4',5,5' positions	PCB-167
2,3,3',4,4',5,5'-HpCB	heptachlorinated biphenyls with chlorine substituted in the 2,3,3',4,4',5,5' positions	PCB-189
(a) International Union of Pure and Applied Chemistry, (http://iupac.chemsoc.org/general/about.htm)

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emissions inventory

Hazardous Air Pollutants List and Reporting Thresholds